The preparation of foods in commercial and residential kitchens results in wastes of many types. The largest volume of waste in such an environment is water which is used in the preparation of many vegetable and animal foodstuffs. The unused portions of the ingredients are often flushed down the kitchen sink drain, or processed into smaller particles by a garbage disposal unit. Vegetable oils and animal fats are also by-products of preparing meals. By most accounts, these wastes are often flushed down the sink drain and left to be processed by the municipal utility companies. The environmental concerns of flushing such organic material down the drain are significant, in that the waste liquid must be processed by sewage or water treatment plants before being reused or released to rivers, lakes, or the like. If not treated, the fats, oils and grease (FOG) can build up in private and city drain systems and require eventual cleaning which is costly and often interrupts service to the users. It is of primary importance that the FOG by-products not be flushed down drains into septic systems, as this can interrupt or stop the bacterial action and render the system unusable. As such, it is a better practice to require each user to remove the FOG liquids from the waste water before the water is released to the community or private water treatment system. The FOG liquid can be recycled to produce usable by-products, or otherwise processed and returned to the environment as a biodegradable material.
The disposal of wastes down the drain by residents of homes and apartments has generally been an acceptable practice to date. The residents are often urged not to place FOG products down the drain, but such practice is voluntary. As noted above, the processing of FOG products in waste water by waste water treatment authorities becomes more costly and requires additional equipment. As the population becomes more dense in city and suburban areas, the treatment and disposal of FOG material becomes more critical, more necessary and more costly. The failure to properly dispose of the FOG material could have an adverse impact on the health in the local community.
In many restaurants and food processing plants, the FOG by-products are removed from the waste water by using a holding tank that is of sufficient size to allow the waste liquid to remain undisturbed long enough so that the FOG liquid rises to the top. An inverted weir located on the bottom portion of the tank allows the waste water to be drained off, while the solids migrate to the bottom of the tank. As the separation process continues, the depth of the FOG liquid increases and leaves less volume in the tank for the waste water and solids. Eventually, the FOG liquid must be drained off and disposed of in a responsible manner so that the tank can again operate efficiently. Periodically, the solids must be removed from the tank manually in order to restore it to the original operating capacity.
Other waste disposal systems are equipped to remove the collected FOG liquid from the separation chamber by either mechanical or hydrostatic means in order to maintain the efficiency of the device at a high level. The problems with the solids and silts are addressed by the use of catch baskets which separate the solids from the waste water. It can be appreciated that with a finer screen in the catch basket less particulate matter passes through, but the catch basket must be manually cleaned more frequently. With a coarse screen, the catch basket requires emptying less frequently, but more particulate matter passes therethrough. The removal of the catch basket by a person is not a pleasant job and thus is often neglected until absolutely necessary. This situation leads to the degradation of the organic solids until they begin to smell, which is unacceptable and undesirable in either the private or commercial setting. The FOG material must be disposed of, and in the restaurants setting, can be a daily routine carried out by staff members.
From the foregoing, it can be seen that a need exists for a waste disposal system which separates the waste water and solids from the FOG liquid, and then automatically disposes of the waste waster and solids together, while allowing the FOG liquid to be collected and removed from the system when needed. Another need exists for a waste disposal system that requires no electrical driven apparatus in order to provide the separation capabilities, and no moving parts that would otherwise wear and require maintenance or replacement. Yet another need exists for a waste disposal system that employs the hydrostatic forces available in such type of system to provide the force and suction necessary to carry the solids with the waste water to the utility drain system, and to also provide the force to drain the FOG liquid into a container for disposal thereof.